Metric System Study Notes

Metric System Overview

• The metric system is the most widely used system of measurement internationally.

Basic Units of Measurement

• Meter (m): The metric unit for length. Commonly used for measurements of height, circumference, and wound size.

• Gram (g): The metric unit for weight.

• Liter (L): The metric unit for volume, where liter is abbreviated with an uppercase 'L'.

Metric Notation

• The metric system operates on multiples of 10, allowing for straightforward conversions.

• Size Indication: The prefix attached to basic units indicates the size and scale of the measurement.

• Example: A meter divided by 1,000 is equal to one millimeter (mm).

Common Metric System Prefixes

• Length:

  • kilo- (k): kilometer (km)

  • Conversion: $1 ext{ km} = 1,000 ext{ m}$

  • centi- (c): centimeter (cm)

  • Conversion: $1 ext{ cm} = 0.01 ext{ m}$

  • milli- (m): millimeter (mm)

  • Conversion: $1 ext{ mm} = 0.001 ext{ m}$

  • micro- (mc): micrometer (mcm)

  • Conversion: $1 ext{ mcm} = 0.000001 ext{ m}$

• Weight/Mass:

  • kilo- (kg): kilogram (kg)

  • centi- (cg): centigram (cg)

  • milli- (mg): milligram (mg)

  • micro- (mcg): microgram (mcg)

• Volume:

  • kilo- (kL): kiloliter (kL)

  • centi- (cL): centiliter (cL)

  • milli- (mL): milliliter (mL)

  • micro- (mcL): microliter (mcL)

Rules for Metric Notation

Rule 4-1

• Use Arabic numerals with decimals to represent any fractions.

  • Example: Write 1.25 g to represent 1 1/4 g.

Rule 4-2

• If the quantity is less than 1, include a 0 before the decimal point.

  • Delete any unnecessary zeros.

  • Example: Instead of writing .750, write 0.75.

Rule 4-3

• Write the unit after the quantity with a space between the unit and the quantity.

  • Example: Write 30 mg, not mg 30 or 30mg.

Rule 4-4

• Use lowercase letters for metric abbreviations, except for liters which is represented by an uppercase 'L'.

  • Example: Write mg, not MG; Write mL, not ml.

Rule 4-5

• To convert a quantity from one metric unit to another:

  1. For larger to smaller units, move the decimal point to the right.

  2. For smaller to larger units, move the decimal point to the left.

Practice Problems

• Practice converting measurements between units:

  1. Convert 4 L to mL.

  2. Convert 75 mm to meters.

Additional Conversion Practice

1. Convert 4 g = x mg

2. Convert 6.5 L = x mL

3. Convert 7,586 mm = x m

4. Convert 455 mg = x g

5. Convert 10,689 mL = x L

6. Convert 1.5 m = x cm

Answers for Additional Conversions

• 4 g = 4,000 mg

• 6.5 L = 6,500 mL

• 7,586 mm = 7.586 m

• 455 mg = 0.455 g

• 10,689 mL = 10.689 L

• 1.5 m = 150 cm

Apply Your Knowledge

• What is the correct metric notation for:

  1. Six-hundredths kilograms? Answer: 0.06 kg

  2. Five hundred sixty-five centimeters? Answer: 565 cm

  3. Fourteen and one-half liters? Answer: 14.5 L